Keeping the rest of the damage model as-is, I'd love to have the wing radiators on spits, 109s, and the belly radiators on huricanes, p51s, and so forth, be actual targets. If hit, you get the exact same damage code as a normal radiator hit, only the graphics start leaking from that spot instead of the prop itself (which makes no sense!).
I wouldn't mind planes with 2 radiators being able to cruise on reduced power without burning up totally (i.e. maybe minimum settings will keep it pegged red, but won't kill it?)